Question

If a polynomial function f(x) has roots 3 and square root of 7, what must also be a root of f(x)

Answer 1

x = -
`√(7)`

Explanation:

Radical roots occur in pairs, that is

x =
`√(7)` is a root then so is x = -
`√(7)`

Answer 2

-√7 = -2.64

Explanation:

The polynomial function has roots. The first root is 3 and the second is √7.

When we have a square root that means that we get two roots from the same number but one is negative and the other is positive. For example, if we have:

√x² = ±x

Because we can have:

(-x)² = x², or

(x)²=x².

So a square root always gives us two answers, one negative and the other positive.